*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:Inter,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:#f8fafc;color:#0f172a}
a{color:inherit}
.container{width:min(1180px,calc(100% - 48px));margin-inline:auto}
.guide-hero{padding:74px 0 64px;background:radial-gradient(circle at 86% 18%,rgba(37,99,235,.14),transparent 29%),linear-gradient(180deg,#fff,#f8fafc);border-bottom:1px solid #e2e8f0}
.guide-badge{display:inline-flex;align-items:center;gap:8px;color:#1d4ed8;background:#eff6ff;border:1px solid #bfdbfe;border-radius:999px;padding:7px 11px;font-size:12px;font-weight:800;letter-spacing:.08em}
.guide-hero h1{max-width:880px;margin:18px 0;font-size:clamp(40px,6.2vw,66px);line-height:1.04;letter-spacing:-.05em}
.guide-hero h1 span{color:#2563eb}
.guide-hero> .container>p{max-width:760px;margin:0;color:#475569;font-size:19px;line-height:1.7}
.guide-meta{display:flex;flex-wrap:wrap;gap:9px 18px;margin-top:24px;color:#64748b;font-size:14px}
.guide-meta strong{color:#334155}
.guide-section{padding:68px 0}
.guide-section.white{background:#fff;border-block:1px solid #e2e8f0}
.section-heading{margin-bottom:28px}
.section-heading span{color:#2563eb;font-size:12px;font-weight:800;letter-spacing:.08em}
.section-heading h2{margin:8px 0 10px;font-size:clamp(30px,4vw,42px);line-height:1.12;letter-spacing:-.035em}
.section-heading p{max-width:720px;margin:0;color:#64748b;font-size:17px;line-height:1.7}
.guide-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}
.guide-card{display:flex;flex-direction:column;padding:30px;background:#fff;border:1px solid #e2e8f0;border-radius:18px;text-decoration:none;box-shadow:0 10px 28px rgba(15,23,42,.045);transition:transform .2s ease,border-color .2s ease,box-shadow .2s ease}
.guide-card:hover{transform:translateY(-3px);border-color:#93c5fd;box-shadow:0 15px 34px rgba(15,23,42,.08)}
.guide-card .eyebrow{color:#2563eb;font-size:12px;font-weight:800;letter-spacing:.08em}
.guide-card h2,.guide-card h3{margin:12px 0 10px;font-size:25px;line-height:1.25;letter-spacing:-.025em}
.guide-card p{margin:0 0 22px;color:#64748b;line-height:1.7}
.guide-card .read-link{margin-top:auto;color:#2563eb;font-weight:800}
.tool-row{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}
.tool-link{padding:24px;background:#f8fafc;border:1px solid #e2e8f0;border-radius:16px;text-decoration:none}
.tool-link:hover{border-color:#93c5fd;background:#eff6ff}
.tool-link strong{display:block;margin-bottom:7px;font-size:17px}
.tool-link span{color:#64748b;font-size:14px;line-height:1.55}
.article-shell{display:grid;grid-template-columns:minmax(0,760px) 280px;gap:56px;align-items:start;padding:58px 0 80px}
.article-body{min-width:0}
.article-body h2{margin:48px 0 14px;font-size:32px;line-height:1.2;letter-spacing:-.03em}
.article-body h2:first-child{margin-top:0}
.article-body h3{margin:30px 0 10px;font-size:22px;line-height:1.3}
.article-body p,.article-body li{color:#334155;font-size:17px;line-height:1.78}
.article-body ul,.article-body ol{padding-left:24px}
.article-body li+li{margin-top:9px}
.formula-box,.example-box,.action-box{margin:28px 0;padding:24px 26px;border-radius:16px}
.formula-box{background:#0f1f4b;color:#fff}
.formula-box strong{display:block;margin-bottom:9px;color:#93c5fd;font-size:13px;letter-spacing:.07em}
.formula-box p{margin:0;color:#fff;font-size:20px;font-weight:750}
.example-box{background:#eff6ff;border:1px solid #bfdbfe}
.example-box h3{margin-top:0;color:#1e3a8a}
.example-box p:last-child{margin-bottom:0}
.checklist{counter-reset:steps;display:grid;gap:16px;margin:25px 0}
.check-item{position:relative;padding:23px 24px 23px 72px;background:#fff;border:1px solid #e2e8f0;border-radius:16px;box-shadow:0 7px 22px rgba(15,23,42,.035)}
.check-item:before{counter-increment:steps;content:counter(steps);position:absolute;left:22px;top:22px;width:34px;height:34px;display:grid;place-items:center;border-radius:10px;background:#2563eb;color:#fff;font-weight:850}
.check-item h3{margin:0 0 7px;font-size:20px}
.check-item p{margin:0;font-size:16px}
.action-box{background:#fff;border:1px solid #cbd5e1;box-shadow:0 10px 30px rgba(15,23,42,.05)}
.action-box h2{margin-top:0}
.action-links{display:flex;flex-wrap:wrap;gap:11px;margin-top:20px}
.primary-link,.secondary-link{display:inline-flex;align-items:center;justify-content:center;padding:12px 17px;border-radius:10px;text-decoration:none;font-weight:800}
.primary-link{background:#2563eb;color:#fff}
.secondary-link{background:#fff;color:#1e40af;border:1px solid #bfdbfe}
.article-aside{position:sticky;top:96px}
.toc{padding:23px;background:#fff;border:1px solid #e2e8f0;border-radius:16px}
.toc strong{display:block;margin-bottom:12px}
.toc a{display:block;padding:8px 0;color:#475569;text-decoration:none;font-size:14px;line-height:1.4}
.toc a:hover{color:#2563eb}
.aside-note{margin-top:16px;padding:20px;background:#eff6ff;border:1px solid #bfdbfe;border-radius:16px;color:#334155;font-size:14px;line-height:1.6}
.faq-list details{background:#fff;border-bottom:1px solid #e2e8f0}
.faq-list summary{cursor:pointer;padding:18px 0;font-size:17px;font-weight:750}
.faq-list p{margin:0;padding:0 0 18px}
@media(max-width:900px){.article-shell{grid-template-columns:1fr;gap:28px}.article-aside{position:static;order:-1}.toc{display:none}.tool-row{grid-template-columns:1fr}.guide-grid{grid-template-columns:1fr}}
@media(max-width:600px){.container{width:min(1180px,calc(100% - 28px))}.guide-hero{padding:56px 0 50px}.guide-hero h1{font-size:39px}.guide-hero> .container>p{font-size:17px}.guide-section{padding:52px 0}.article-shell{padding:38px 0 60px}.article-body h2{font-size:27px}.article-body p,.article-body li{font-size:16px}.check-item{padding:20px 18px 20px 62px}.check-item:before{left:16px;top:18px}.formula-box,.example-box,.action-box{padding:21px}.action-links{flex-direction:column}.primary-link,.secondary-link{width:100%}}